Saving Australia’s migratory shorebirds from extinction

A major discovery about habitat changes that are threatening many of Australia’s migratory bird species has led to widespread policy changes and influenced coastal development decisions both in Australia and abroad.

By Ron Hohenhaus

For shorebirds that nest on the Arctic tundra, Australia is located at the other end of a long and perilous international flight path that researchers call the East Asian-Australasian flyway. Each year millions of birds migrate up and down this biological superhighway.

But recent surveys have highlighted a worryingly rapid decline in the numbers of these global wanderers visiting Australia.

Thanks to the efforts of a multinational team of bird researchers, coupled with decades of bird counts by volunteer organisations, scientists are starting to better understand the mounting pressures facing birds moving along this great Antipodean aerial route.

The UQ research behind this discovery has had significant and rapid impact on policy reform – directly influencing national policies and a conservation action plan to prevent further decline, and international partnerships to curb coastal reclamation and conserve habitats that are vital to these feathered visitors.

Millions of migratory birds visit Australia each year from distant breeding grounds, some up to 11,000 kilometres away in remote Arctic Circle habitats in Siberia and Alaska.

UQ research, which analysed 25 years of monitoring data from citizen science groups around Australia, has shown that many migratory species are in extremely rapid decline and much closer to extinction than previously thought.

For example, the eastern curlew has declined by 80 per cent in 30 years. While this is the most dramatic decline, the research has uncovered systematic declines across many migratory species, suggesting a dramatic threat is operating somewhere along the birds’ migration routes.

In May 2015, the Australian Government listed the eastern curlew and the curlew sandpiper as Critically Endangered under the Environment Protection and Biodiversity Conservation Act 1999, with another six migratory shorebirds also listed as nationally threatened the following year.

But research conducted by Professor Richard Fuller and his team at UQ’s School of Biological Sciences may have uncovered the fundamental reason that fewer and fewer migratory shorebirds visit Australian shores each year.

By analysing hundreds of satellite images, the researchers found that two-thirds of the key intertidal habitat used by the birds as they passed through the Yellow Sea – located between China and South Korea – had disappeared since the 1950s.

While this was a clear candidate cause of the migratory bird declines, no definitive analysis linked the habitat loss to the bird declines.

However, this changed when Professor Fuller’s ecological research showed, for the first time, that the species that have been declining fastest in Australia are the same species that rely heavily on mudflats in the Yellow Sea to feed and rest during their migration.

The strong statistical support for this discovery meant that the epicentre of many species’ decline could now confidently be located in the Yellow Sea.

Professor Fuller says his research emphasises the need for coordinated conservation.

“Australia has signed agreements with China, Korea and Japan to protect migratory birds, yet the birds have continued to decline,” he says.

“Every country along the migration route of these birds must protect habitat and reduce hunting to prevent the birds declining further or even going extinct.

“We’re encouraged that China and Korea have recently begun the process of listing parts of the remaining Yellow Sea habitats as World Heritage sites.”

Following the discovery, the Government of the People’s Republic of China recently placed a moratorium on coastal reclamation.

Scientific data provided by UQ as well as Dutch, Chinese and other international researchers is thought to have played a part in influencing this policy change.

The UQ research has also had significant impact within Australia.

For example, within Queensland, the state government has used UQ data in planning tools to guide development decisions.

UQ Honours student Madeleine Stigner’s research on disturbance to migratory shorebirds also led to the Queensland Parks and Wildlife Service initiating and approving a program to implement zoning plans for recreational disturbance to threatened shorebirds, including a partnership with Brisbane City Council to explore new recreational zoning in Moreton Bay – one of the most important locations for migratory shorebirds in Australia.

The UQ-backed research has also been the basis of several BirdLife Australia campaigns – the peak body for bird conservation in Australia – for enhanced environmental protection for migratory shorebirds.

Speaking at the launch of the Australian Government’s Wildlife Conservation Plan for Migratory Shorebirds in 2016, BirdLife Australia CEO Paul Sullivan concluded that “the science is in”, and that urgent conservation action is now needed.

While this national coordination to take action to save these species is a step in the right direction, the immense global flight path involved means that solving this problem requires international scientific cooperation.

And thanks to the influence of UQ research, this is becoming a reality.

For several decades, researchers have been concerned about the critically endangered eastern curlew, which breeds in Russia, China and Mongolia, then escapes the northern winter by moving along East Asian–Australasian flyway.

Citing the UQ research, the Australian Government drafted an international action plan for the eastern curlew, the most threatened of all the migratory species that visit Australia, which was ratified by 22 countries.

The plan was later approved by a meeting of the East Asian–Australasian Flyway Partnership, a body which includes 37 state and non-state agencies working across the eastern curlew’s entire migratory range.

Drafted in close collaboration with UQ researchers, the action plan is now being implemented by nations throughout the East Asian–Australasian flyway.

Professor Fuller is hopeful for the future.

“Science has paved the way for action, and conservation efforts are underway across the flyway,” he says.

“With hard work, we can prevent a mass extinction, and once again see vast numbers of migratory birds gracing our shores.”

Long haul for record-breaking bird

The bar-tailed godwit (Limosa lapponica) holds the record for the longest known non-stop flight. It makes its way from Alaska to New Zealand along the East Asia-Australasia flyway on a journey of some 11,000 km.

To reduce its energy demand along the way, the godwit has evolved the amazing ability to shrink its own gizzard and intestines, while simultaneously increasing its total body fat to about 50 per cent of its bodyweight.

Some bar-tailed godwits have made the trip from Alaska to New Zealand in eight days at an average speed of about 56 km/h.

The story so far

1950s: Earliest indications that migratory shorebirds were starting to decline in some locations.

2002–2016: UQ researchers discover that populations of at least 12 migratory species are declining nationally.

2010: UQ researchers design and lead a full-scale national analysis of migratory shorebird populations, funded by the Australian Government, Queensland Government, Port of Brisbane, and Queensland Wader Study Group, a citizen science organisation that collects monitoring data on shorebirds.

2015: The Australian Government drafts an international action plan for the eastern curlew, which is ratified by 22 countries.